I still think that Harry and Hermione are better off as just friends. I know this is a Harry/Luna Hermione story and while I do read those sometimes in this story, so far, Harry and Hermione seem to be better off as friends. While with Luna, so far, it's seems like Harry is just glad that someone is interested in him as Harry, and not as 'The Boy Who Lived.' I'd really like to see Harry show that he really does love Luna in a romantic sense.
Harry & Hermione haven't explored a relationship as a couple, so they naturally fall into the role as friends.
As Luna has already identified, a lot of what Harry feels for her is simply in response to the affection he's been given freely by her. It honstly isn't hard for a guy with as little experience as Harry to fall head over heels under those circumstances.
He's only just been given a reason to challenge his feelings for her, and only because she's asked him to.
Things are probably going to be quite confusing for Harry.